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Full text of "The manufacture and properties of iron and steel"

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silicon and carbon in the open-hearth furnace by ordinary methods, for a charge can be decarburized with great rapidity by shoveling ore into the furnace continually; the reactions take place and the silicon and carbon are oxidized as fast as can be desired, but this cannot be continued because there is such an absorption of heat that the bath becomes cold. It is difficult to see how the time necessary for decarburization can be shortened by preheating and melting the ore, and having a violent reaction with a consequent chilling. The decarburization itself will take place in less time, but the total time necessary to melt the ore, to complete the reaction, and to heat the charge after the reaction will probably be longer than if the ore were added after the pig-iron is charged.
Table XII-D is condensed from Mr. Talbot's paper showing the history of the metal and slag in the furnace. There are five heats given in full in his paper and one other heat in part, but I have quoted only two, as they are representative of all. Mr. T'albot lays much stress on the gain in weight from the ore, but it is a mistake to regard this as characteristic of the method. Section Xllg will take up this subject, while Sections Xlle and Xllf also bear upon the matter.
Elimination of Sulphur in Talbot Furnace.
Heat.	Hate of Production.		Elimination of Sulphur.	
	Weight of in-gotd; Ibs.	Time from tap to tap. Houn-Min.	Calculated average sulphur in metal charged.	Sulphur in fin-iBhed Bteel.
264 .................	57,405 39,100 39,085 37,410 38,650 191,650 92 tons.	3-50 425 440 4-55 4-30 2220	.041 .048 .058 .054 .049	.038 .038 .050 .050 .054
264 ...... . ..........				
285 ........... . .....				
806...... ...........				
408 ................				
Total ......				
Rate per 24 hours..				
Table XII-E shows that there was very little elimination of sulphur in any of the heats; the slag was kept fluid and not very basic, and under these conditions the furnace will run much faster and make more product than if a better steel is made. Three out of the five heats would not fill the standard American specifications for boiler plate. It may be urged that there was no necessity of